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1989 SC needs to run mid 12s

I recently bought a 1989 Supercoupe five speed. I got it from the original owner and it has 109k miles on it and it needs a clutch. The exterior is fairly nice but the interior is pretty rough, the engine seems to start and run fairly well.

I am entering the car in a local junkyard race and need to run a mid to high 12 second pass to be near the top. I realize this can be a tall order to fill in a supercoupe because of the weight. I originally planned to do this with an older mid 80s 2.3L turbocoupe but those cars have become difficult to find in decent shape. The good news is that because this is a junkyard race, I can remove as much weight as I would like to try to achieve my goal.

I am well versed in making a EEC-IV controlled mustang run and also well versed in ford engine controls in general, I just installed a Holley HP EFI system on my SN95 mustang. While I have owned a turbocoupe, I have never dealt with a Supercoupe before. So I am looking for input from the veterans on weight reduction and secondly, making power. I have read many threads here about making power with these engines, so I have done some simple research on replacing the throttle body, mass air meter, etc. Generally I don't see much talk about reducing weight.

- Can you get a thousand pounds out of one of these cars? I know the IRS is very heavy, the bumpers look very heavy, are there crash bars inside the doors? On Fox body mustangs the door crash bars can be worth 30-40 lbs each

- I have read a lot of the E85 threads and understand the concerns with using it. For running E85, has anyone tried replacing the 30 lb injectors in one of these cars with 42 lb injectors? With E85 requiring 40% more fuel, it seems like you would be "in the ballpark" as long as the fuel pump can keep up. A 255 lph (or even a 340) pump may be in order obviously. Part throttle dirveability is not really a concern as long as it will start and get through the burnout box.

- Is there any way to alter the timing without a chip? I know there is a knock sensor, if you unplug it does the computer immediately retard timing and go into a limp home mode?

- Does anyone want to buy the blower after this things explodes? (just kidding on this one)

Getting 1000lbs out is tough, but doable, especially if you don't care what it looks like. The door crash bars are in there, and are quite heavy, but I would skip cutting the bumper reinforcements out since they really don't weigh that much, and you might want that still there if you crash, especially if you aren't putting a cage in it. Obviously everything in the interior would have to go; seats, dash, carpet, headliner, trim panels, sound deadening, etc. If you can ditch all the glass, there is quite a bit of weight there, but put some back in the form of a rear shock tower brace if you take out the back glass, because it is structural. Removing the IRS is quite involved, so I would skip that. If it is a drag only car, you can get rid of the sway bars and save some weight there. Honestly though, if the rules allow for it, pulling the SC engine out and dropping it into a fox body would be the easiest way to get under 3Klbs.

As far as getting some more power, what are you allowed to do to the car? A blower off a 94/95 SC is a substantial improvement that will still look stock. Leave the timing alone, it is aggressive enough in stock form, and there isn't much to be gained there. A tune to get the air/fuel ratios in line would help a lot though. Also, the stock 30# injectors are basically maxed out in stock form, so any kind of power increase will require larger injectors, and therefore a tune, or at the very least an aftermarket MAF to compensate for the larger injectors.

10% OD pulley
E85
42lb injectors
300lph fuel pump
remove the ACT sensor from the engine, leave it connected
Remove the knock sensor from the engine, leave it connected
Dump the exhaust in front of the rear tire
Replace the cats with some glasspacks (just so you don't go deaf)

I think that's about it.

Originally Posted by Miller

Ya thats why i tape mine down. People think its bc i dont have a moonroof seal (which is true) but its really to keep my roof from ripping off .

10% OD pulley
E85
42lb injectors
300lph fuel pump
remove the ACT sensor from the engine, leave it connected
Remove the knock sensor from the engine, leave it connected
Dump the exhaust in front of the rear tire
Replace the cats with some glasspacks (just so you don't go deaf)

I think that's about it.

Thanks Dave, for the input. Especially on the sensors. I have been lurking here long enough to know that you are an expert on these cars.

Also, a little more info. The race has a gentlemen's agreement on cost of $500. I bought the car for $400 but plan to sell a few of the parts to get my basis down. I plan to run it with just a lead pipe coming off of the factory manifolds. I just want the pipe long enough to make sure my wide band is going to be accurate, IE, I need a good spot to put the sensor and then about a foot after that. I plan on using the wide band to tune it on E85 and then I'll remove it. If the E85 makes things too lean I plan on mixing in some pump gas or possibly higher octane unleaded race gas until the mixture gets close to 11:1 or so. If I am too rich I am going to try a different mass air meter first and then a throttle body, let me know if that is the wrong order to try things in.

Would the 94-95 blower and inlet be worth it if I could dig one up? From what I recall reading here it is worth about 1.5 psi of boost at the same blower speed.

In regard to weight reduction, I am glad the rear window was mentioned, I considered removing it but it sounds like I need to leave it in place, at least at first. I was also considered cutting the trunk floor out with a plasma cutter but if the rear shock towers lack support maybe I should leave that for now as well. I plan to run without a hood for both heat and weight reduction.

I was also considered cutting the trunk floor out with a plasma cutter but if the rear shock towers lack support maybe I should leave that for now as well.

Since the donor is a junker, the body might already be cracked and the original 'support' has long since left the building. Same at the front of the cabin. Legacy cracks hide under that heavy layer of sound deadening I hope you've already noticed. Leave it there...it's holding the body together.

Thanks Dave, for the input. Especially on the sensors. I have been lurking here long enough to know that you are an expert on these cars.

Also, a little more info. The race has a gentlemen's agreement on cost of $500. I bought the car for $400 but plan to sell a few of the parts to get my basis down. I plan to run it with just a lead pipe coming off of the factory manifolds. I just want the pipe long enough to make sure my wide band is going to be accurate, IE, I need a good spot to put the sensor and then about a foot after that. I plan on using the wide band to tune it on E85 and then I'll remove it. If the E85 makes things too lean I plan on mixing in some pump gas or possibly higher octane unleaded race gas until the mixture gets close to 11:1 or so. If I am too rich I am going to try a different mass air meter first and then a throttle body, let me know if that is the wrong order to try things in.

Would the 94-95 blower and inlet be worth it if I could dig one up? From what I recall reading here it is worth about 1.5 psi of boost at the same blower speed.

In regard to weight reduction, I am glad the rear window was mentioned, I considered removing it but it sounds like I need to leave it in place, at least at first. I was also considered cutting the trunk floor out with a plasma cutter but if the rear shock towers lack support maybe I should leave that for now as well. I plan to run without a hood for both heat and weight reduction.

I don't think you really listened to what I said.....

You absolutely cannot run E85 with stock injectors. You need 42's. The additional 40% fuel from the injectors will just about nail AFR. Use an adjustable regulator if you think you need to adjust AFR beyond that. Changing the MAF and/or TB will not do anything positive which is why I didn't mention those. You don't need high octane fuel, just do what I said.

If you can score a 94/5 blower then put it on by all means.

PS, it's gonna blow headgaskets, but that's all part of the game.

Originally Posted by Miller

Ya thats why i tape mine down. People think its bc i dont have a moonroof seal (which is true) but its really to keep my roof from ripping off .

You absolutely cannot run E85 with stock injectors. You need 42's. The additional 40% fuel from the injectors will just about nail AFR. Use an adjustable regulator if you think you need to adjust AFR beyond that. Changing the MAF and/or TB will not do anything positive which is why I didn't mention those. You don't need high octane fuel, just do what I said.

If you can score a 94/5 blower then put it on by all means.

PS, it's gonna blow headgaskets, but that's all part of the game.

Don't get me wrong, you are coming through loud and clear on the 42s. I have screwed around with E85 on the mustangs enough to know that I could never get away with it on the stock 30 lb injectors with the boost pressure these cars make.

I am putting a clutch in the car this weekend, then I'll do the 42s, wide band and fuel pump. Will report back soon after.

Don't get me wrong, you are coming through loud and clear on the 42s. I have screwed around with E85 on the mustangs enough to know that I could never get away with it on the stock 30 lb injectors with the boost pressure these cars make.

I am putting a clutch in the car this weekend, then I'll do the 42s, wide band and fuel pump. Will report back soon after.

Going cheap, get the AFR, a good fuel pump you'll need anyway and turn the static pressure up to 70. That'll get you about like 40s out of the stock injectors (I know Dave... I know... but it'll last 10 minutes)

Honestly, best bang for the buck is a head gasket set, pull the heads and port them. Even with stock valves and cam, you can get about 30-40 hp with about 4 hrs grinding. A better set of springs and 1 step colder plugs gapped at .035" will get more consistent RPMs over 4500. You're going to blow one of the stock gaskets in about 3 and a half seconds under power anyway, so might as well fix it now.

Ditch the AC compressor, lines, dryer, condenser, yank all the ABS brake stuff and put standard brakes from a normal Tbird. Pretty much all the dash, radio and heater box could go too. Pull the packing tray in the trunk and ditch the ride control computer and ABS computer along with any speaker/sub parts back there. If you're not worried about looks, leave the bumper covers off and pull all the ground effects.

I have to agree on the ported heads. Especially on the tight budget you are on as they cost nothing to do yourself. Port the blower while it is off too( again costs nothing vs buying a 94/95 blower and reportedly will flow about the same if done correctly) Changing the head gaskets only makes sense in this situation. The port work will not be seen. Then you can tell them it is "stock". I was amazed at the difference between the last two engines I had in the car, only difference being self ported heads. You are going to have to drive the car like you stole it to even come close to meeting the ET goal you have set, even with massive weight reduction. Concentrate on making as much free HP as possible and use the money to setup the suspension properly. All the HP in the world is useless if it doesn't get to the ground!

I have to agree on the ported heads. Especially on the tight budget you are on as they cost nothing to do yourself. Port the blower while it is off too( again costs nothing vs buying a 94/95 blower and reportedly will flow about the same if done correctly) Changing the head gaskets only makes sense in this situation. The port work will not be seen. Then you can tell them it is "stock". I was amazed at the difference between the last two engines I had in the car, only difference being self ported heads. You are going to have to drive the car like you stole it to even come close to meeting the ET goal you have set, even with massive weight reduction. Concentrate on making as much free HP as possible and use the money to setup the suspension properly. All the HP in the world is useless if it doesn't get to the ground!

Do you know of any threads on here about head and blower porting? Or do you know of any site with pics of the head ports? I have no problem cleaning them up. In fact, if they do come off I will clean them up, install new valve springs (or shim the stock junk), use ARP studs and probably do some roller rockers. All of those are out of sight mods that are fairly cheap. Would you guys mill the heads if they come off? I know stock compression is ridiculously low but have no idea of deck thickness.

Search function is your friend here. Plenty of ported blower pics here. Several threads discussing porting heads also. The arp and roller rockers are overkill for what you are trying to accomplish and cost money. eBay is your friend here. Lots of clearance items for Sc's if you dig and are patient.

Search function is your friend here. Plenty of ported blower pics here. Several threads discussing porting heads also. The arp and roller rockers are overkill for what you are trying to accomplish and cost money. eBay is your friend here. Lots of clearance items for Sc's if you dig and are patient.

I have checked out the threads, it is just that I have never seen the head ports, so I am wondering what they look like. I have done my fair share of barnyard head porting on the stock SBF stuff. Now the blower porting pictures on the other hand, I have seen those and understand the difference between the early M90 and the later 94/95 M90 so I think I can make some improvements there if the blower comes off.

The roller rockers probably are overkill but if the head ports are a problem then I'd think the rockers and their increase in effective duration at .050" lift are going to help. Besides, the factory SBF Cobra pedestal mount roller rockers can be had for about $100 around here, that is dirt cheap horsepower to me.

Hopefully all of this is a non issue though, I'm going to pray every night before going to sleep that my head gaskets live a long and fruitful life. Yea, I know, you guys will laugh at that idea. I know the gaskets are crap. lol

The outer intake ports aren't that much different than the Sbf. The center port has a double pushrod bulge( one is actually a head bolt) to deal with. The exhaust is much better than a Sbf and will easily show you what needs to be done if you have even a basic knowledge of porting.

Well we got her up on the lift this weekend and tore her all the way down to the back of the block. We thought for sure that we had a clutch problem and expected the disc to come out in a couple of pieces, we had a hell of a noise going on that you could feel in the tranny and it was tough to shift. Unfortunately we got all the way to the flywheel and had no obvious indicator of a problem besides the fact that the shifter had two of the three bolts to the shift tower loose.

We now think our noise is probably valvetrain related. The engine holds good oil pressure but has a consistent knock. It pulls about 15" of vacuum at idle (from what I understand, 18-20" is normal) and has an intermittent miss in one cylinder that you can hear through the (now wide open to atmosphere) manifolds. The knock isn't like any spun rod bearing or wrist pin knock I have ever heard, it is more like someone is hitting something with a hammer. A stethoscope seemed to point to the driver's side valve cover. We are going to investigate next weekend, with a full set of intake gaskets on hand just in case we have to replace some lifters. Luckily the lifters are the same as the roller SBF so I have quite a few spares, of course I threw away a whole set of nice used SBF lifters a few weeks back (it never fails).

Having never tore into one of these cars, I was amazed at the stock exhaust which is absolutely shameful for a performance car.

We do have a new clutch and slave cylinder now though, so it was not a wasted effort.